00490nas a2200121 4500008004100000245016000041210006900201260001200270300001200282490000700294100001900301856004800320 2003 eng d00aSystematics of the Neritilia rubida complex (Gastropoda: Neritilidae): three amphidromous species with overlapping distributions in the Indo-Pacific0 aSystematics of the iNeritilia rubidai complex Gastropoda Neritil c08/2003 a273-2840 v691 aKano, Yasunori uhttps://neritopsine.myspecies.info/node/24101953nas a2200157 4500008004100000245010800041210006900149260001500218300001400233490000800247520143700255100001901692700001901711700001701730856004801747 2002 eng d00aMajor adaptive radiation in neritopsine gastropods estimated from 28S rRNA sequences and fossil records0 aMajor adaptive radiation in neritopsine gastropods estimated fro c2002 Dec 7 a2457-24650 v2693 aA well-supported phylogeny of the Neritopsina, a gastropod superorder archaic in origin, radiated ecologically and diverse in morphology, is reconstructed based on partial 28S rRNA sequences. The result (Neritopsidae (Hydrocenidae (Helicinidae + Neritiliidae) (Neritidae + Phenacolepadidae))) is highly congruent with the fossil records and the character distribution of reproductive tracts in extant taxa. We suggest that the Neritopsina originated in subtidal shallow waters, invaded the land and became fully terrestrial at least three times in different clades, by the extinct Dawsonellidae in the Late Palaeozoic and by the Helicinidae and Hydrocenidae in the Mesozoic. Invasion of fresh- and brackish waters is prevalent among the Neritopsina as the Jurassic and freshwater ancestory is most probable for helicinids. The Phenacolepadidae, a group exclusively inhabiting dysoxic environments, colonized deep-sea hydrothermal vents and seeps in the Late Cretaceous or Early Cenozoic. Submarine caves have served as refuges for the archaic Neritopsidae since the Early to Middle Cenozoic, and the marine neritopsine slug Titiscania represents a highly specialized but relatively recent offshoot of this family. The Neritiliidae is another clade to be found utilizing submarine caves as shelter by the Oligocene; once adapted to the completely dark environment, but some neritiliids have immigrated to surface freshwater habitats.1 aKano, Yasunori1 aChiba, Satoshi1 aKase, Tomoki uhttps://neritopsine.myspecies.info/node/24200410nas a2200109 4500008004100000245010400041210006900145300001200214490000700226100001900233856004800252 2002 eng d00aAnatomy and systematics of the submarine-cave gastropod Pisulina (Neritopsina: Neritiliidae)0 aAnatomy and systematics of the submarinecave gastropod iPisulina a365-3840 v681 aKano, Yasunori uhttps://neritopsine.myspecies.info/node/24300449nas a2200121 4500008004100000245011900041210006900160300001200229490000600241100001900247700001300266856004800279 2000 eng d00aTaxonomic revision of Pisulina (Gastropoda: Neritopsina) from submarine caves in the tropical Indo-Pacific.0 aTaxonomic revision of iPisulinai Gastropoda Neritopsina from sub a107-1290 v41 aKano, Yasunori1 aKase, T. uhttps://neritopsine.myspecies.info/node/26401212nas a2200133 4500008004100000245008600041210006900127260001600196300001200212490000600224520078100230100001901011856004801030 2009 eng d00aHitchhiking behaviour in the obligatory upstream migration of amphidromous snails0 aHitchhiking behaviour in the obligatory upstream migration of am c2009 Aug 23 a465-4680 v53 aMigratory animals endure high stress during long-distance travel in order to benefit from spatio-temporally fluctuating resources, including food and shelter or from colonization of unoccupied habitats. Along with some fishes and shrimps, nerite snails in tropical to temperate freshwater systems are examples of amphidromous animals that migrate upstream for growth and reproduction after a marine larval phase. Here I report, to my knowledge, the first example of 'hitchhiking' behaviour in the obligatory migration of animals: the nerite snail Neritina asperulata appears to travel several kilometres as minute juveniles by firmly attaching to the shells of congeneric, subadult snails in streams of Melanesian Islands, presumably to increase the success rate of migration.1 aKano, Yasunori uhttps://neritopsine.myspecies.info/node/23002528nas a2200133 4500008004100000245009800041210006900139260001300208300001400221490000800235520208400243100001902327856004802346 2006 eng d00aUsefulness of the opercular nucleus for inferring early development in neritimorph gastropods0 aUsefulness of the opercular nucleus for inferring early developm c2006 Sep a1120-11360 v2673 aThe early ontogeny of gastropods (i.e., planktotrophic vs. nonplanktotrophic) may be inferable from the morphology of the protoconch in adult shells. The protoconch consists of both embryonic and larval shells in species with planktotrophic development; the embryonic shell forms in the intracapsular period and the succeeding larval shell gradually develops during the larval period. In nonplanktotrophic species, on the other hand, there is no additional growth of the larval shell and the protoconch consists exclusively of a relatively large embryonic shell formed prior to hatching. This "shell apex theory" has been applied to many species of shell-bearing gastropods, but biotic and abiotic erosion of the apex often prevents detailed examination of the protoconch and subsequent inferences about ontogeny. I examined the gastropod operculum to test its utility for predicting developmental mode, drawing on the Neritimorpha as model taxa. Most aquatic members of Neritimorpha were found to bear an operculum with a clearly demarcated nucleus; SEM observations reveal four types of nuclei, which correspond to different types of protoconch morphologies and observed ontogenies for the study species. The nucleus is secreted before metamorphosis, fits into the shell aperture of the larva, and reflects early ontogeny as morphology, as does the protoconch. Moreover, the apparently organic (rather than calcareous) composition of the nucleus makes it nearly invulnerable to erosion and very advantageous, compared to the protoconch, in this ecologically diverse group, whose habitats range from freshwater streams and mangrove swamps to rocky shores and deep-sea hydrothermal vents. The measurements of the nucleus are also valuable for taxonomic purposes, especially in the species identification of veliger larvae and juvenile snails. On the other hand, the opercular nuclei of the Caenogastropoda and Heterobranchia are often eroded away in adult individuals; even if present, the morphology of the nuclei does not seem to clearly reflect early ontogeny in those groups.1 aKano, Yasunori uhttps://neritopsine.myspecies.info/node/235